Re: [PATCH 6/6] can: esd_usb: Improved decoding for ESD_EV_CAN_ERROR_EXT messages

[Vincent MAILHOL]

On Sat. 9 Jul. 2022 at 03:14, Frank Jungclaus <frank.jungclaus@xxxxxx> wrote:
> As suggested by Vincent I spend a union plus a struct ev_can_err_ext

The canonical way to declare that something was suggested by someone
else is to use the Suggested-by tag.

Also, this particular change was suggested by Marc, not by me ;)
https://lore.kernel.org/linux-can/20220621071152.ggyhrr5sbzvwpkpx@xxxxxxxxxxxxxx/

> for easier decoding of an ESD_EV_CAN_ERROR_EXT event message (which
> simply is a rx_msg with some dedicated data).

Suggested-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>

> Signed-off-by: Frank Jungclaus <frank.jungclaus@xxxxxx>
> ---
>  drivers/net/can/usb/esd_usb.c | 20 ++++++++++++++------
>  1 file changed, 14 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/net/can/usb/esd_usb.c b/drivers/net/can/usb/esd_usb.c
> index 09649a45d6ff..2b149590720c 100644
> --- a/drivers/net/can/usb/esd_usb.c
> +++ b/drivers/net/can/usb/esd_usb.c
> @@ -126,7 +126,15 @@ struct rx_msg {
>         u8 dlc;
>         __le32 ts;
>         __le32 id; /* upper 3 bits contain flags */
> -       u8 data[8];
> +       union {
> +               u8 data[8];
> +               struct {
> +                       u8 status; /* CAN Controller Status */
> +                       u8 ecc;    /* Error Capture Register */
> +                       u8 rec;    /* RX Error Counter */
> +                       u8 tec;    /* TX Error Counter */
> +               } ev_can_err_ext;  /* For ESD_EV_CAN_ERROR_EXT */
> +       };
>  };
>
>  struct tx_msg {
> @@ -134,7 +142,7 @@ struct tx_msg {
>         u8 cmd;
>         u8 net;
>         u8 dlc;
> -       u32 hnd;        /* opaque handle, not used by device */
> +       u32 hnd;   /* opaque handle, not used by device */
>         __le32 id; /* upper 3 bits contain flags */
>         u8 data[8];
>  };
> @@ -228,11 +236,11 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
>         u32 id = le32_to_cpu(msg->msg.rx.id) & ESD_IDMASK;
>
>         if (id == ESD_EV_CAN_ERROR_EXT) {
> -               u8 state = msg->msg.rx.data[0];
> -               u8 ecc   = msg->msg.rx.data[1];
> +               u8 state = msg->msg.rx.ev_can_err_ext.status;
> +               u8 ecc   = msg->msg.rx.ev_can_err_ext.ecc;
>
> -               priv->bec.rxerr = msg->msg.rx.data[2];
> -               priv->bec.txerr = msg->msg.rx.data[3];
> +               priv->bec.rxerr = msg->msg.rx.ev_can_err_ext.rec;
> +               priv->bec.txerr = msg->msg.rx.ev_can_err_ext.tec;
>
>                 netdev_dbg(priv->netdev,
>                            "CAN_ERR_EV_EXT: dlc=%#02x state=%02x ecc=%02x rec=%02x tec=%02x\n",

Yours sincerely,
Vincent Mailhol